OVERFLOW OF RED RIVER OF THE NORTH. 5 
The glaciers eroded the hills that then existed and filled the valleys. 
Rocks wer.e ground into gravel and sand. As the glaciers receded to 
the north the materials deposited by them were further reduced by 
waves and currents in the lake. The streams brought down silt which 
was deposited in the lake. In this manner were formed the topo- 
graphical features and the soils now found in the watershed of the 
Red River. 
SOIL. 
The soils throughout the former glacial lake bed are deep, heavy, 
finely divided, well-compacted mixtures of clay, loam, and small pro- 
portions of very fine sand. For the first foot or more this mixture is 
deeply blackened by decayed organic matter. The soils of the valley 
are classified by the United States Bureau of Soils (Bulletin 96, 1913) 
as the Fargo series of soils. Six types are mentioned: Clay loam, 
fine sandy loam, loam, fine sand, clay, and silt loam comprise the prin- 
cipal areas. In their natural condition most of these soils are poorly 
drained. All are fertile and, when drained, admirably adapted to 
agricultural purposes. The soil of the upper levels of the watershed 
is less uniform in quality and somewhat less productive than that of 
the central valley, but through drainage, clearing, and proper farm- 
ing methods practically all can be developed into excellent farm 
land. Along the edges of the central plain are found moraines and 
shore lines of the former lake. These are long, low ridges of sand 
, or gravel from a few hundred feet to a half-mile in width. Such 
land has less agricultural value than any other in the watershed. 
WATERSHEDS. 
The watersheds of the Red River and its tributaries are shown in 
figure 1, and their areas are given in Table 1. 
The Red River watershed has been subdivided as indicated on the 
map and in the table, for the purpose of comparing the precipitation, 
temperature, topography, soil, vegetation, and natural and artificial 
drainage of the different portions, as affecting run-off in the valley. 
UTILITY OF THE WATERCOURSES. 
Of the various ways in which the Red River and its tributaries 
prove useful and valuable to the community the more important are 
the removal of excess water, water supply, sewage disposal, water 
power, and recreation v Commercial navigation although in earlier 
days of great importance has decreased until at present it is insig- 
nificant. Commercial fishing is carried on to some extent in differ- 
ent parts of the watershed but the industry is of minor importance 
in the State boundary waters. Irrigation by water drawn from the 
streams has been considered, but it has been found that where con- 
